How to repair cellular problems on your iPhone 4 (CDMA)

Replacing it is a relatively straight-forward DIY repair that isn't too difficult. If you're out of warranty, it's also a much cheaper option than purchasing a new iPhone or paying for a replacement.

Disclaimer: As with any repair, iMore cannot be held responsible for any damage you may do to your device. It's also worth considering that opening up your device to perform any repair or modification can and will void your Apple warranty. If you don't feel comfortable opening your device, don't. Use extreme care and caution when performing a repair on any device.

What you need for a DIY CDMA (Verizon or Sprint) iPhone 4 cellular replacement

iMore recommends using only quality and genuine parts from a reputable supplier like iFixYouri. They have quality parts, tools, and much more for all your repair needs.

CDMA iPhone 4 (please note there ARE internal differences between the GSM and CDMA models - this guide strictly deals with the CDMA model - in the US, that means Verizon or Sprint)

Power off your iPhone 4

Before performing any repair, always power off your device before removing any screws or parts.

Remove the back

First remove the bottom 2 dock connector screws in your iPhone 4. Use your five point security screwdriver for this as all versions of the CDMA iPhone 4 have security screws in the dock connector.

To remove the back simply slide the back upwards and lift it off gently.

Set the back and 2 dock connector screws aside.

Organize your screws

It's very important to make sure you remember where you are pulling screws from, so place them in an arrangement that you'll understand and remember. I normally lay them out the same way every time I disassemble a device so I remember where they came from and how they go back in. They're all different sizes so trying to figure out where they go if you get them mixed up probably won't be fun.

Remove the battery

To remove the battery you'll need to remove the #00 screw holding the battery clip in place. Remove this screw located to the bottom left of the battery.

The metal clip on the battery is what clips the battery to the logic board. You'll need to pop this clip up with your plastic pry tool. Simply stick the end of your pry tool underneath the clip and gently pull upwards until it unfastens from the logic board.

To remove the battery, I do not recommend using the plastic pull tab. There is quite a bit of adhesive underneath the battery and the tab will normally just rip off or you can bend the battery. Instead, run your pry tool along the right side of the battery and break the adhesive that way. Once the battery is free from the adhesive, you can pull the battery out of the phone. There are no other connectors holding it in.

I typically fold the plastic tab over while working on the iPhone 4 to keep it out of the way while I'm disassembling parts. It's not necessary but convenient.

Remove the grounding clip

To the left of where you disconnected the battery you'll see another screw holding in a grounding clip over the end of the cellular antenna. We'll need to remove it.

Unscrew the one screw holding the grounding clip in place with your #00 Phillips screwdriver.

Gently lift the grounding clip out of the device. It's very tiny as you can see above. Take care not to misplace it or lose it.

Remove the dock connector shield and disconnect the cable

There is a shield held on with two screws covering the dock connector cable. Remove the two screws holding it in place and set the shield and screws aside, remembering where they came from. (They are labeled as screw 1 & 2 in the photo above.)

Next, use your pry tool to pry up the actual dock connector cable. Be careful as there is adhesive holding the cable in place as well. Peel back the adhesive gently to free the cable.

Unclip the antenna from the logic board

Underneath where you removed the grounding clip, you'll see a tiny circular cable. This is your antenna cable. You'll need to unclip it from the logic board.

Take the edge of your pry tool or spudger and gently pry up the circular head to detach it from the logic board.

You'll notice the cable is wound around some metal brackets. Just gently guide it out of the brackets with your pry tool and finger. It's attached to the speaker assembly. Once you've finished unwinding it from the brackets, you can leave it where it is for now.

Remove the speaker assembly

The cellular antenna is held down to the speaker assembly with 2 screws and some adhesive. We'll need to remove the speaker assembly to remove the antenna from the iPhone.

To remove the speaker assembly you have two #00 screws to remove. They sit to the right and the left of the speaker assembly. The left screw will have a tiny triangular shaped plastic spacer under the screw. Set it aside with the screw as well for re-assembly. If you lose this, your speaker assembly will not sit correctly.

Gently lift the speaker assembly out of your device and set it aside.

Remove the old cellular antenna and install the new one

Remove the 2 screws holding the cellular antenna down and peel it off the speaker assembly. You can see by comparing the new cellular antenna and the one on the speaker assembly how the adhesive peels off and how it is held in.

Reassemble your iPhone 4

To re-assemble your CDMA iPhone 4, you can either follow these directions in reverse order or watch the video above, which includes reassembly instructions.

And... done!

Reboot your iPhone 4; hopefully, you should now have signal bars. Now it's time to let us know how it went!